administration to test positive. austin said he's had three covid shots and experiencing mild symptoms. meg oliver has more including big news on boosters for kids. >> as more children enter the hospital affected with the omicron variant, the f.d.a. says those as young as 12 can get a third dose or booster of the pfizer vaccine. despite surging covid cases, millions of children return to school including in new york city. >> i'm going to tell you what's going to happen day to day, we are staying open. we are going to do everything that we have to do to keep our schools open. >> reporter: the city is doubling the number of substitutes tested in each school and providing an additional 2 million test kids. >> how are you? >> reporter: in washington, d.c. the number of new cases jumped 330% in the last two weeks. the nation's second largest school system los angeles unified ordered students and staff to undergo mandatory covid